Binding sites of lipophilic quinone and quinone analogue inhibitors in the cytochrome b₆f complex of oxygenic photosynthesis

The main structural features of the cytochrome b₆f complex, solved to 3.0–3.1 Å (1 Å=10⁻¹⁰ m) in the cyanobacterium Mastigocladus laminosus and the green alga Chlamydomonas reinhardtii are discussed. The discussion is focused on the binding sites of plastoquinone and quinone analogue inhibitors discerned in the structure. These sites mark the pathway(s) of quinone translocation across the complex.